McDonald et al.: Spatial and seasonal abundance of Cynoscion arenarius and C. nothus off the coast of Texas 
35 
gration of adults are limited by pass size, configuration, 
and distance. However, there are also global factors 
such as the population abundance within offshore areas 
that affect inshore abundance, which decreases from 
north to south along the Texas coast. In turn, offshore 
abundance is likely related to hydrological factors such 
as depth and salinity, such that inshore populations of 
sand seatrout are not independent of offshore abiotic 
conditions. However, offshore abundance may be equally 
affected by the presence and availability of estuarine 
nursery areas, because estuaries are highly productive 
and offer an alternative location for the growth of age-1 
individuals. This supposition was not explicitly tested in 
our study because all offshore gulf areas in this study 
were located near estuarine passes. However, it is clear 
that offshore and inshore abundance are closely linked, 
and the presence of a pass between the two likely af- 
fects abundance of local populations as a whole. 
Acknowledgments 
We thank biologists of the Texas Parks and Wildlife 
Department-Coastal Fisheries Division (TPWD-CF), spe- 
cifically the countless dedicated technicians and biologists 
who collected the data as part of their routine monitoring 
activities that are funded in part by Federal Aid in Sport- 
fish Restoration Grant (FRM-34). We thank B. Balboa for 
his expertise and time. Improvements to the first draft 
were provided by M. Fisher (TPWD), B. Karel (TPWD), 
C. Williams (TSU), and wife Christa (of Dusty McDon- 
ald), and three anonymous reviewers. This research 
project was funded in part by dedicated funds from a 
Federal Aid in Sportfish Restoration Grant (F-158-R). 
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